counter = 100  # 赋值整型变量
miles = 1000.0  # 浮点型
name = "John"  # 字符串

print(counter)
print(miles)
print(name)

a = b = c = 1

a, b, c = 1, 2, "john"

var1 = 1
var2 = 10

s = "a1a2···an"  # n>=0

s = 'abcdef'
print(s[1:5])

str = 'Hello World!'

print(str)  # 输出完整字符串
print(str[0])  # 输出字符串中的第一个字符
print(str[2:5])  # 输出字符串中第三个至第六个之间的字符串
print(str[2:])  # 输出从第三个字符开始的字符串
print(str * 2)  # 输出字符串两次
print(str + "TEST")  # 输出连接的字符串

letter = 'checkio'

print(letter[1:4: 2])

t = ['a', 'b', 'c', 'd', 'e']

print(t[1:3])
print(t[:4])
